This invention relates to a gas turbine combustion chamber.
More specifically this invention relates to a gas turbine combustion chamber having an annular combustion chamber confined by an outer and an inner combustion chamber wall and provided with several fuel injection nozzles.
As is known from the state of the art, fuel is injected, or sprayed, into the annular combustion chamber space of annular combustion chambers via several. circumferentially distributed fuel Injection nozzles. In this process, a conical fuel curtain is mixed with an airflow swirling concentrically around the fuel injection nozzles. The vortex of fuel and air thus produced is concentric around the central axis of the fuel injection nozzle.
The known design of the combustion chamber annulus is disadvantageous in that large regions between the fuel injection nozzles lack an immediate supply of air and fuel. Thus, the area of the combustion chamber annulus is not fully employed for the formation of a mixture of fuel and air which is homogenous right from the beginning. The merely “locally” concentric injection of fuel around the fuel injection nozzles quite inadequately utilizes the space of the annular combustion chamber.
The locally injected, relatively large masses of fuel require a certain time, and thus a certain space, to provide a relatively coarse, ignitable and fairly uniformly distributed mixture. Consequently, the length of the annular combustion chamber must be dimensioned appropriately relative to the flow direction.
Furthermore, the problems described impair the combustion efficiency of the fuel-air mixture and involve considerable effort to further reduce nitrogen oxides. Moreover, the relatively erratic formation of the fuel-air mixture results in pressure, flow and temperature variations over the circumference of the annular combustion chamber.
In addition, due to the erratic injection of fuel, the temperature profile at the combustion chamber exit is relatively inhomogeneous in the circumferential direction, resulting in thermal problems in the area of the turbine and vibrations caused by different densities and flow velocities.